The following table indicates prior art that appears to be relevant to the invention disclosed:
U.S. PatentsPat. No.Kind CodeIssue DatePatentee8,401,236B2Mar. 19, 2013Kassouf et al.7,941,935B2May 17, 2011Khan7,913,404B1Mar. 29, 2011Smith6,799,376B1Oct. 5, 2004Voeller et al.6,718,646B2Apr. 13, 2004Corghi6,522,400B1Feb. 18, 2003Horn6,282,799B1Sep. 4, 2001Warkotsch6,082,011Jul. 4, 2000Philips, III5,675,408Oct. 7, 1997Samuelsson et al.5,367,778Nov. 29, 1994O'Hara5,157,838Oct. 27, 1992Sims5,056,231Oct. 15, 1991Alusick et al.4,942,667Jul. 24, 1990Fournier4,347,668Sep. 7, 1982Johnston3,691,642Sep. 19, 1972Nolte et al.
The commercial trucking industry's profit margin is heavily dependent on the cost of fuel and tires. These two consumables can both be conserved by reducing rolling resistance of the truck and trailer wheels. The simplest way to reduce rolling resistance is to maintain alignment of the axles which are prone to becoming misaligned under heavy loading.
Many commercial trucking businesses are not equipped with alignment tools necessary to maintain their fleet of trucks and trailers. Instead they routinely send their vehicles to alignment shops that use complex and expensive alignment systems such as described in U.S. Pat. No. 8,401,236. The high cost associated with this type of alignment system, coupled with rising fuel and tire prices, has led to the development of simple, inexpensive, and portable alignment systems such as described in U.S. Pat. No. 7,913,404. However this type of alignment system is more prone to measurement error due to its dependence on less reliable measurement references and constraints.
The commercial trucking industry needs an axle alignment system that is simple, inexpensive, portable, and less susceptible to measurement error than alignment systems currently offered by the market. An alignment system that achieves these objectives will be disclosed.